A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5905-01-652-3073
NSN 5930-01-307-8414
NSN 2925-01-055-7607
NSN 5935-01-175-1859
NSN 6150-01-569-2790
NSN 6150-01-137-9654
NSN 6220-00-736-2617
NSN 5935-01-620-0151
NSN 6240-01-244-7668
NSN 5975-00-243-6434
NSN 5999-01-250-2623
NSN 6130-01-503-5512